Unable to send SMTP via MDaemon with TLS and app password enforced

I am attempting to get eM Client 10.0.3530 configured with my email address which is self-managed on an MDaemon Email Server which I own.

At the MDaemon server, I have configured the account to allow OTP and have set up multiple app passwords for the account. OTP is set to “Allow Two-Factor Auth”, however “Require Two-Factor Auth” is not enabled.

Microsoft Outlook 365 Version 2409 Build 16.0.18025.20030 (current version at time of writing) can connect and send email via SMTP port 465 using TLS with authentication using the account name and app password without issue. Similarly, the 9Folders client on Android can also connect to the SMTP service on port 465 using the app password without issue.

I’ve tried setting up eM Client to use the same app password as those two other clients, and I have also tried setting up a new app password. None of these options work. If I disable the requirement to use an app password on the MDaemon server for that particular account, and configure eM Client to use the account name and password, it is able to connect to the SMTP service on port 465 without issue. When I attempt the diagnostics in eM Client, it repeatedly assures me the password is wrong.

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I’ve got a bunch of other screenshots showing the configuration of Outlook, and eM Client, but of course the forum thinks I’ve never use the Internet before so it won’t let me post more than one piece of media.

I am at a loss - does anyone have any good suggestions?

Apparently there is a setting in MDaemon to disable APOP/CRAM-MD5 authentication for the SMTP server.

Disabling that option allows eM Client to successfully connect with an app password.